Electric cable.



m. 7|6,|55. Patented Deo. |6, 1902.

J; H. WEST.

ELECTRIC CABLE.

"(Application filed Sept. 21, 1901.) (No Model.)

2 Sheets-Sheot I.

No. 7|6,|55. Patented Dec. l6; I902.v

J. H. WEST.

ELECTRIC CABLE (Application filed Sept. 21. 1901.)

(No Model.) 2 Sheets-Sheet 2.

UNITED STATES PATENT OFFICE.

JULIUS HENRIK WEST, OF BERLIN, GERMANY.

ELECTRIC CABLE.

1PEC1FIGATION forming part of Letters Patent No. 716,155, dated December16, 1902.

Application filed September 21, 1901. Serial No. 76,127. (No model.)

To all whom, it may concern.-

Be it known that I, JULIUS I-IENRIK WEsT,

' letters of reference marked thereon, which form a part of thisspecification.

Figure 1 is a side elevation, and Fig. 2 a section, of a known form ofcable. Fig. 3 is an elevation, and Fig. 4C a section, of a cable made inaccordance with this invention, showing two insulated wires. Figs. 5, 6,and 7 show sections carrying four, six, and eight wires, respectively.Fig. 8 shows the machine-made strip to form the cable, and Fig. 9 acable of four Wires assembled. Fig. 10 is a section showing seven zigzagstrips having insulation around each strip and an outer covering for theentire cable, and Fig. 11 is a side elevation showing a covered zigzagstrip.

For the purpose of reducing the constants of the dielectrics used inelectric cables as much as possible instead of using a paper strip woundaround the wires it has been proposed by Breisig (Elektroiechm'scheZeitschrt'ft, 1899, pages 129 and 130) to use apaper strip, arranged asshown in Fig. 1, folded in the shape of a meander and provided at eachside with notches, Fig. 2, in which two wires are laid and are securedby means of an external covering. When such a strip is used, theconstruction of the cables is rendered very difficult and cannot easilybe effected in a machine. These difficulties can, however, be obviatedby using a strip folded in a zigzag manner, as shown in Fig. 3, insteadof a strip as shown in Fig. 1. Fig. 4 is a cross-section correspondingto Fig. 3. Such a zigzag strip can also be used for insulating four,six, or eight wires from one another, as shown in Figs. 5, 6, and 7, andif the corners be rounded so that an approximately circularcross-section is obtained, sevcircuits.

eral such bundles of wires can be twisted together and yet have noinductive action on one another and waste no space.

In a cable according to Fig. 6 the wires a and a form one circuit, thewires 6 Z) a second, and c c a third. The two circuits 1) b and c o arearranged in such a way that they have no inductive action on each other;but the circuits a and a are influenced by the two other In order toprevent this disturbing action, all that is necessary is to change therelative positions of the wires (1 and a -t'. e., to connect a of theone section of the cable with a of the adjoining section,and vice versa,and a of the first section with a of the adjoining section at regularintervals when the several lengths of the cable are connected togetherin laying it. In a similar manner in a cable according to Fig. 7, inwhich one strip of paper serves for separating eight wires, inductiondisturbances can be obviated by retaining the circuits at and a and cand c in their relative positions and changing the relative positions ofthe wires of the two other circuits 1) b and d and d at regularintervals. Cables constructed in this manner have a very lowelectrostatic charge. The average constant of the dielectric is reducedalmost to 1, since mainly air is used as an insulator and the quantitiesof paper between the wires are extremely small. The constructiondescribed has the additional advantage that without increasing the costof insulation in an appreciable degree the wires can be placed as farapart as desired, so that it is possible to produce cables which aresuitable for interurban and submarine telephone wires. For this purposea narrow strip of paper of suitable length is folded by mechanical meansin the manner shown in Fig. 8, the pressed'and folded strip is provided,by means of circular saws or cutters,with four, six,or eight notches, asshown in Figs. 5, 6, or 7, and the corners are rounded off by means of aplane or a cutter. The insulating-strip thus prepared is placed in acable-machine and a Wire is inserted into each notch, whereupon whilethe wires are being drawn forward the paper strip is drawn apart bymeans of simple devices until it assumes the form shown in Fig. 9.Thereupon a strong cotton or silk thread is Wound around the wires andholds them in position. If necessary, such a bundle of wires can becovered with a wide strip of paper 1', as shown in Fig. 10. The zigzagseparating-strip and also the outer covering do not require to be ofpaper, but may be of any other suitable material. The required number ofsuch bundles is then twisted together and is covered with paper 1) andthen with impregnated fibrous material '5 and finally with a leadcovering Z. If necessary, a further protectingarmature is placed on theexterior.

Having thus described my invention, what I claim as new therein, anddesire to secure by Letters Patent of the United States of America, is-

1. An electric cable comprising a zigzag strip of insulating materialprovided with notches and Wires in said notches, substantially asdescribed.

2. An electric cable comprising a zigzag strip of insulating materialhaving notches at the sides and at the bends of'said strip, and wires insaid notches, substantially as described.

3. An electric cable comprising a notched zigzag strip of paper andwires in said notches, substantially as described.

4. An electric cable comprising a notched zigzag strip of paper, wiresin said notches and an insulating-covering, substantially as described.

5. An electric cable, composed of elements twisted together, eachelement comprising a zigzag strip of paper having notches in its sidesand in its bends, wires in said notches and an insulating-covering,substantially as described.

6. An electric cable comprising a continuous zigzag strip of insulatingmaterial having rounded corners and a plurality of notches in its sidesand in its bends, and wires held in said notches by a cord of insulatingfibrous material, substantially as described.

7. An electric cable, composed of a plurality of elements twistedtogether, each element comprising a zigzag strip of insulating materialhaving rounded corners and notches in its sides and bends, wires held insaid notches by a cord of insulating material wound around the whole,and a covering of insulating material, a covering of paper for theelements twisted together and one of impregnated fiber, substantially asdescribed.

In testimony that I claim the foregoing as my invention I have signed myname in presence of two subscribing witnesses.

JULIUS HENRIK WEST. Witnesses:

HENRY HASPER, WOLDEMAR HAUPT.

